Chapter 9 Week 3 Immunity copy 2 (dragged).pdf

Stress and Disease Chapter 9 Stress Perceived or anticipated threat that disrupts a person’s well-being or homeostasis May stem from psychological/emotional (fear, social rejection), physical (dramatic temperature changes, abuse), or physiological (infection, inflammation) stimuli that trigge...

Stress and Disease Chapter 9 Stress Perceived or anticipated threat that disrupts a person’s well-being or homeostasis May stem from psychological/emotional (fear, social rejection), physical (dramatic temperature changes, abuse), or physiological (infection, inflammation) stimuli that trigger the stress response Allostasis “Stability through change”; the link between stress and disease Brain continuously monitors for future events and anticipates what is required from neuroendocrine and autonomic systems Allostatic overload - Overactivation of adaptive systems, may lead to clinical pathophysiology and increase of the chance of disease - Highly individualized (different for everyone) Regulation of the Hypothalamic-Pituitary-Adrenal System A key stress hormone relationship is the regulation of the hypothalamic-pituitary-adrenal (HPA) system. Stress → activates the hypothalamus to secrete corticotropin-releasing hormone (CRH), which then bind to receptors on anterior pituitary cells that produce adrenocorticotropic hormone (ACTH) ACTH circulates through the blood to the adrenal glands & results in the release of cortisol Cortisol Secreted during stress & reaches all tissues Stimulates gluconeogenesis (formation of glucose for energy) → Elevates the blood glucose level Affects protein metabolism Abnormal elevations linked to obesity, sleep deprivation, lipid abnormalities, hypertension (HTN), diabetes, atherosclerosis, and loss of bone density Secretion during stress inhibits initial inflammatory effects Promotes resolution and repair Used therapeutically as powerful anti-inflammatory/immunosuppressive agents Elevated levels may decrease innate immunity and increase autoimmune responses Sympathetic Nervous System & Parasympathetic Nervous System SNS Arousal of the sympathetic nervous system occurs simultaneously with the HPA system during stress. Releases: - Norepinephrine & epinephrine - Epinephrine causing shunting of blood to heart, lungs, and brain - Increased heart rate, BP - Catecholamines PNS Balances the sympathetic nervous system and influences adaptation to stressful situations. Has opposite effects; slows HR via vagus nerve The Alarm Reaction A patient experiences a stressor that activates the stress response. What is a physiological effect seen related to the release of catecholamines into the bloodstream? A. Increased heart rate B. Bronchoconstriction C. Increased insulin release D. Decreased blood pressure Immunity & Stress Stress directly related to proinflammatory cytokines Link between stress, immune function, and disease/cancer Immune system affected by neuroendocrine factors Stress response decreases T-cell cytotoxicity and B-cell function Coping Take care of yourselves!! Nursing school can be, and is, quite stressful. Ensure you are doing what you need to fill your cup and to be kind to yourself. I am always here to chat :) Clinical Round Topics & Groups - Metabolic Acidosis Kelly & Blessing - Metabolic Alkalosis - Respiratory Acidosis Kaelin & Sim - Respiratory Alkalosis Danica & Kaylie - Hyponatremia - Hypernatremia Layla & Megan - Hypokalemia - Hyperkalemia - Hypermagnesemia - Hypomagnesemia - Hypercalcemia - Hypocalcemia